I I IMPOSITAE. 



Vol.111. 



9. Senecio frigidus Less. Arctic Senecio. 

 Fig. 4618. 



Senecio frigidus Less. Linnaea 6: 239. 1831. 



Perennial, more or less tomentose, or becoming 

 glabrous when old; stem slender, 6'-i2' high, bearing 

 a solitary head (rarely 2 or 3) t'-i' broad. Basal 

 and lower leaves spatulate or obovate, i'-2' long, peti- 

 oled, obtuse, repand-dentate or entire; stem leaves 

 oblong to linear-lanceolate, obtuse or acute, sessile, 

 mostly entire, smaller ; involucre broadly campanu- 

 late, about 7" high, its bracts lanceolate, acute, with 

 no exterior smaller ones; rays 10-16, 6"-io" long, 

 3-toothed, linear-oblong, or cuneate at the base; 

 achenes glabrous or sparingly pubescent ; pappus 

 white. 



Labrador and arctic America to Alaska, 

 eastern Asia. Summer. 



Also in north- 



10. Senecio Jacobaea L. Tansy Ragwort. 

 Staggerwort. Fig. 4619. 



Senecio Jacobaea L. Sp. PI. 870. 1753. 



Perennial by short thick rootstocks, somewhat 

 woolly, or glabrous; stems stout, simple, or 

 branched above, 2-4 high, very leafy. Stem 

 leaves 2-3-pinnatifid, 2'-8' long, the lower peti- 

 oled, the upper sessile, the lobes oblong-cuneate, 

 dentate or incised; basal leaves lyrate-pinna- 

 tifid ; heads very numerous, 6"-8" broad, short- 

 peduncled in large compact corymbs; involucre 

 narrowly campanulate, about 23" high, its bracts 

 linear-lanceolate, acute, green, or tipped with 

 black, usually with a few subulate outer ones ; 

 rays 12-15; achenes of the disk-flowers pubes- 

 cent, those of the rays glabrous; pappus white. 



In waste places. Newfoundland and Nova Scotia to 

 Maine and Ontario, and in ballast about New York 

 and Philadelphia. Adventive from Europe. Stave- 

 wort. Cankerweed Kettle-dock. St. James'-wort. 

 Felonweed. Fairies'-horse. Ragweed. Saracen's-com- 

 pass. July-Sept. 



-'- 1>, 



11. Senecio antennariifolius Britton. 

 paw Ragwort. Fig. 4620. 



Cat's- 



Senecio antennariifolius Britton, in Britt. & Brown. 111. 

 Fl. 3: 478. 1898. 



Perennial, tufted in mostly large clumps; stems 

 slender, 8'-i8' high, loosely white-woolly. Leaves 

 nearly all basal, commonly numerous, oval to spatu- 

 late, angulately few-toothed or entire, mostly obtuse, 

 narrowed into a petiole as long as the blade or longer, 

 densely white-tomentose beneath, green and finally 

 glabrous above, l'-2l' long; stem leaves small, spatu- 

 late, laciniate. or the upper narrowly linear and en- 

 tire; heads several, corymbose, slender-peduncled, 

 rathed less than 1' broad; rays golden-yellow, showy ; 

 involucre 3" high, white-woolly ; achenes glandular- 

 pubescent. 



Stony hillsides, mountains of Virginia and West Vir- 

 ginia. May-June. 



